This invention relates to a hydro-automatic valve for the control of branchings of the distribution piping of a sprinkling irrigation system on steep grounds, which can be used in stationary and semi-stationary sprinkling systems for the irrigation of farm land.
A known hydro-automatic valve for controlling branches of distribution piping is described in Bulgarian Author's Certificate No. 36064. The known valve system comprises a valve disposed inside a cylindrical housing with inlet and outlet holes from and to a basic distribution piping, and an outlet hole to a branch piping, and a cylinder with a piston. The space within the cylinder underneath the piston is connected to an additional control piping of the irrigation system, while the space above the piston is connected to an air-water reservoir and, via a throttling diaphragm, to the inlet hole of the cylindrical housing. The drawbacks of the known hydro-automatic valve are: unreliable control of the valve at slow formation of the signal for reduced pressure in the inlet holes; the impossibility of switching over the valve at the presence of residual hydrostatic pressure in the inlet holes of the valve (for example as a result of the change in elevation of the ground on which the irrigation system is mounted); the complicated design of the valve due to the presence of a water-air reservoir and a throttling diaphragm; the need for purifying the water from mechanical impurities since their presence in the cylinder and throttling diaphragm causes malfunctions; and the complicated design of the slide valve, which results in increased size.